I've done quite a bit of goggleing and have really only found RoundCube as a talked about alternative. I've played with the demo and agree that it's better than squirrelmail, however I'm just not 100% on it.
I use open-exchange for a domain I have with a different host and like it's features.
Say I would want to install open-exchange rather than RoundCube -- will I lose all historical mail? I emailed dreamhost tech and they said that there is no way to back-up my dreamhost email. They assured me that if I install RoundCube via the quick install that I will not lose any mail. My biggest fear is that I will lose all historical email when installing Open-Exchange.
Anyone have any experience with installing alternatives to squirrelmail?